It's no secret that devices inside a PC case are affected by their environment. One of our articles proved three years ago that TV tuners depend on such system parameters as frequencies and quality of a power supply unit. Inexorable pace of technical progress has led to the situation when a single graphics card consumes as much power as an old system unit. There is no surprise this hasn't been ignored by manufacturers wanting to minimize the effect of possible noise on devices in neighboring slots.

Our product under review was presented at Computex'2007, codenamed iFilter, as an accessory for graphics cards installed in Home Theatre PCs. The company was only considering to supply it as a stand-alone product at that time. However, it does not matter how this product got to end users. Let's talk about technical characteristics.

HIS iClear is a card to be installed into any PCI-Express slot (1x, 4x, 16x). The manufacturer recommends installing this filter between a graphics card and a device to protect from noise. Even though it looks simple (just a PCB and several capacitors), the black color, the gold-plated plank, and a huge logo produce an impression of an expensive product.

As it's problematic to use the iClear with a graphics card that has a two-slot cooling system and a PCI-Express device because of the layout of slots on the motherboard, we used two combinations of our TV tuner and a graphics card:

We have chosen these TV tuners, because they use Philips TDAA8275AC1 semiconductor HF units, inferior to the main competitors. As our objective is to see how a TV tuner works in unfavorable conditions, the tests were conducted with a weak 53-55 dB (microvolt) signal.

As our generator produces a signal in special meter bands 73 - 82 and S-01 - S-18, these bands are represented on separate graphs. Thus, these results are not a sterling amplitude-frequency characteristic. However, you may plot it on your own using the data published below.

We traditionally publish several images obtained with different signal-noise ratios according to our test procedure. We'll start with 35 dB, as the minimum acceptable level for comfortable TV reception.

SNR = 35

SNR = 32

SNR = 30

SNR = 20

SNR = 17

Results of the KWorld Plus TV Hybrid PCI and the NVIDIA GeForce 8800GTX

There are no miracles here, signal-noise ratios remain the same in most channels. Nevertheless, we can still notice the effect of the filter on the TV tuner, even though the absolute difference in signal-noise ratio within 2 dB does not allow to speak of an apparent positive effect.

Surprise! Despite the difference in power of these graphics cards, the iClear demonstrates higher efficiency in this combination. Perhaps, it has to do with the interface of this TV tuner or the motherboard layout, but we cannot discard these results. While 9% with 38 dB and 34.8 dB do not make a visual difference, the same result with a lower signal-noise ratio can have a noticeable effect.

Conclusions

Out of doubt, HIS iClear is hardly necessary for normal operation of a computer. Ideologically, it's a modding component. However, unlike various LEDs and transparent inserts, this filter can indeed produce a positive effect on PC operation, no matter how small it may be in a given configuration. The afterlife of the iClear and its possible counterparts will depend on many factors, including retail prices (prime costs of this device must be low). But we can say one thing for sure - bundling such components with graphics cards can make them more attractive.